.drawer {
    width: 300px;
    height: 100%;
    border: 1px solid black;
    position: fixed;
    top: 0;
    right: 0;
    background-color: aliceblue;
    transition: all 400ms;
    z-index: 100;
}

.drawer .on-off {
    width: 35px;
    height: 35px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 40px;
    position: absolute;
    top: 20px;
    left: -45px;
    background-color: aliceblue;
    cursor: pointer;
    transition: all 400ms;
}